On Tue, Aug 11, 2020 at 06:35:03PM -0700, Andrew Morton wrote:
> From: Rikard Falkeborn <rikard.falkeborn@gmail.com>
> Subject: lib/test_bits.c: add tests of GENMASK
> 
> Add tests of GENMASK and GENMASK_ULL.
> 
> A few test cases that should fail compilation are provided under #ifdef
> TEST_GENMASK_FAILURES
> 
> [rd.dunlap@gmail.com: add MODULE_LICENSE()]
>   Link: http://lkml.kernel.org/r/dfc74524-0789-2827-4eff-476ddab65699@gmail.com
> [weiyongjun1@huawei.com: make some functions static]
>   Link: http://lkml.kernel.org/r/20200702150336.4756-1-weiyongjun1@huawei.com
> Link: http://lkml.kernel.org/r/20200621054210.14804-2-rikard.falkeborn@gmail.com
> Link: http://lkml.kernel.org/r/20200608221823.35799-2-rikard.falkeborn@gmail.com
> Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
> Signed-off-by: Randy Dunlap <rd.dunlap@gmail.com>
> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
> Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
> Cc: Emil Velikov <emil.l.velikov@gmail.com>
> Cc: Syed Nayyar Waris <syednwaris@gmail.com>
> Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Emil Velikov <emil.l.velikov@gmail.com>
> Cc: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Kees Cook <keescook@chromium.org>
> Cc: Linus Walleij <linus.walleij@linaro.org>
> Cc: William Breathitt Gray <vilhelm.gray@gmail.com>
> Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>

> ---
> 
>  lib/Kconfig.debug |   11 ++++++
>  lib/Makefile      |    1 
>  lib/test_bits.c   |   75 ++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 87 insertions(+)
> 
> --- a/lib/Kconfig.debug~bits-add-tests-of-genmask
> +++ a/lib/Kconfig.debug
> @@ -2236,6 +2236,17 @@ config LINEAR_RANGES_TEST
>  
>  	  If unsure, say N.
>  
> +config BITS_TEST
> +	tristate "KUnit test for bits.h"
> +	depends on KUNIT
> +	help
> +	  This builds the bits unit test.
> +	  Tests the logic of macros defined in bits.h.
> +	  For more information on KUnit and unit tests in general please refer
> +	  to the KUnit documentation in Documentation/dev-tools/kunit/.
> +
> +	  If unsure, say N.
> +
>  config TEST_UDELAY
>  	tristate "udelay test driver"
>  	help
> --- a/lib/Makefile~bits-add-tests-of-genmask
> +++ a/lib/Makefile
> @@ -342,3 +342,4 @@ obj-$(CONFIG_PLDMFW) += pldmfw/
>  # KUnit tests
>  obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o
>  obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o
> +obj-$(CONFIG_BITS_TEST) += test_bits.o
> --- /dev/null
> +++ a/lib/test_bits.c
> @@ -0,0 +1,75 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Test cases for functions and macros in bits.h
> + */
> +
> +#include <kunit/test.h>
> +#include <linux/bits.h>
> +
> +
> +static void genmask_test(struct kunit *test)
> +{
> +	KUNIT_EXPECT_EQ(test, 1ul, GENMASK(0, 0));
> +	KUNIT_EXPECT_EQ(test, 3ul, GENMASK(1, 0));
> +	KUNIT_EXPECT_EQ(test, 6ul, GENMASK(2, 1));
> +	KUNIT_EXPECT_EQ(test, 0xFFFFFFFFul, GENMASK(31, 0));
> +
> +#ifdef TEST_GENMASK_FAILURES
> +	/* these should fail compilation */
> +	GENMASK(0, 1);
> +	GENMASK(0, 10);
> +	GENMASK(9, 10);
> +#endif
> +
> +
> +}
> +
> +static void genmask_ull_test(struct kunit *test)
> +{
> +	KUNIT_EXPECT_EQ(test, 1ull, GENMASK_ULL(0, 0));
> +	KUNIT_EXPECT_EQ(test, 3ull, GENMASK_ULL(1, 0));
> +	KUNIT_EXPECT_EQ(test, 0x000000ffffe00000ull, GENMASK_ULL(39, 21));
> +	KUNIT_EXPECT_EQ(test, 0xffffffffffffffffull, GENMASK_ULL(63, 0));
> +
> +#ifdef TEST_GENMASK_FAILURES
> +	/* these should fail compilation */
> +	GENMASK_ULL(0, 1);
> +	GENMASK_ULL(0, 10);
> +	GENMASK_ULL(9, 10);
> +#endif
> +}
> +
> +static void genmask_input_check_test(struct kunit *test)
> +{
> +	unsigned int x, y;
> +	int z, w;
> +
> +	/* Unknown input */
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(x, 0));
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(0, x));
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(x, y));
> +
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(z, 0));
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(0, z));
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(z, w));
> +
> +	/* Valid input */
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(1, 1));
> +	KUNIT_EXPECT_EQ(test, 0, GENMASK_INPUT_CHECK(39, 21));
> +}
> +
> +
> +static struct kunit_case bits_test_cases[] = {
> +	KUNIT_CASE(genmask_test),
> +	KUNIT_CASE(genmask_ull_test),
> +	KUNIT_CASE(genmask_input_check_test),
> +	{}
> +};
> +
> +static struct kunit_suite bits_test_suite = {
> +	.name = "bits-test",
> +	.test_cases = bits_test_cases,
> +};
> +kunit_test_suite(bits_test_suite);
> +
> +MODULE_LICENSE("GPL");
> _